Bypass turbofan engines may have problems with fan stability. This particular engine produces two exhaust flows. The first flow is an engine core flow, which is discharged from a core flow nozzle after passing through a core engine. The second flow is a fan flow, which passes through an annular passageway formed by a core engine nacelle surrounding the core engine and fan duct. The cross-sectional areas through which these two flows pass (i.e., the engine core flow throat area at the core flow nozzle and the fan flow throat area at the fan nozzle) are optimized for specific operating conditions. However, the operating conditions change. For example, during takeoff, more thrust is needed from the engine than during cruise flight. More thrust is generated by passing more gases through the fan duct at the fan nozzle resulting in the increased velocity of the gas flow. Variable area fan nozzles may be used to address the fan stability. A variable area fan nozzle include movable petals that may be actuated outwardly to enlarge the nozzle area and, as a result, to reduce the exhaust velocity. Conversely, these petals may be actuated inwardly to reduce the nozzle area of the fan nozzle and, as a result, to increase the exhaust velocity. Fan stability issues can arise when the nozzle area is not large enough causing back pressure to be too high. A variable area fan nozzle can increase the nozzle area to alleviate this back pressure and eliminate fan instabilities.